The patients suffering from AIDS, organ transplant recipients and bone marrow transplant recipients have high risk of fungal infections. The total number of these types of patients is increasing in recent years and there is need to develop effective antifungal agents. There are various antifungal agents used to fight against fungal infections out of which fluconazole is an important azole antifungal. It is orally active and has low toxicity so it is widely used but its extensive use has resulted in emergence of fluconazole-resistant fungal strains. It is therefore necessary to develop novel antifungal agents effective against resistant strains. Worldwide efforts to obtain fluconazole analogues effective against resistant strains have resulted in synthesis of many novel azole antifungals. The structure-activity relationship studies have shown that presence of one triazole ring, halogenated phenyl ring and tertiary alcoholic oxygen functionality in fluconazole are necessary structural features essential for activity exhibited by fluconazole. The present invention seeks to provide novel azole antifungal compounds comprising benzothiazinone, benzoxazinone or benzoxazolinone moieties and process thereof as an effort to come up with antifungal agents with broad spectrum of antifungal activity. Fluconazole analogues have been reported to exhibit antifungal activity in the literature. Some of the references describing synthesis and antifungal activity of fluconazole analogues are:
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The compounds described in the present invention are novel compounds with enhanced antifungal activity and hence the protection is sought for the same.